Manufacture of azo dyestuffs



5 param OFFICE GEORGE HOLLAND ELLIS, or sroNDoN, NEAR DERBY, EN LAND, ASSIGNOR 'ro OELAN- ESE CORPORATION or AMERICA, A conronnrron or DELAWARE MANUFACTURE on n20 nYEsrUFrs No Drawing. Application filed August 2, 192a, SeriaI No. 297,099, and n1 Great Biz-tainA 'ugust17.1927.

This invention relates to the manufacture of new azo dyestuffs and more particularly applicable to materials made of or containing cellulose acetate or other organic esters or ethers of cellulose.

Thenew azo dyestuffs according to the present invention are preparedby diazotizing an anthraqulnone derivative containing a diazotizable ammo group and coupling with an amino naphthoic acid or a side-chain or nuclear substitution product thereof.

In producing the new azo dyestuffs the amin-o-anthraquinone or derivative thereof may be diazotized, for example 1n solution in strongacids or in aqueous suspension in the presence of mineral acid. The diazo solution obtained may then be diluted if neces- I saryand coupled with the amino naphth-oic acid or derivative thereof.

aration of the new azo dyestuffs of the present invention, but are not to be cons dered as 11miting the invention in any way.

Ewample 44.6 parts of alpha-amino-anthraquinone are dissolved in .l5O-parts of sulphuric acid and precipitated on to 4000 parts of ice.

15 parts of sodium nitrite, dissolved in cold water, are then added to effect dlazotization. The whole is stirred hour cold.

48.8 parts of the hydrochloride of Q-amino- 3-naphthoic acid are dissolved in water and the solution of the diazotized amine run in slowly, with stirring, the temperature of coupling being 510 C. The requisite quantity of sodium acetate solution is'then run in slowly to neutralize mineral acid. Coupling commences immediately, and is complete in about 2 hours. The dyestuffis isolated in the usual manner. It dyes in bluish-red shades and has the probable formula 1 1 TH: $00K V ample 'quinone are dissolved in 500 parts ofsulphuric acid and then poured on to ice. 15 parts of;

sodium nitrite, dissolved in cold water are thenadded, and the whole stirred 30 minutes.

The diazo solution is then coupled with 2- amino-3 naphthoic acid in a manner exactly as inEXample. 1 above.

The following examplesillustrate the prepdian'lino anthraquinbne monodiazor shades while ,B-aminO-anthraquinOne with the same coupling component gives a dyestuif yleldmg orange-red shades.

'Instead of 2-amino-3-naphthoic,acid used above as thecoupling component, other amino naphthoio acids mayfbe employed, for ex- 4r-Amino-l-naphthoic acid.

5- Amino-l-naphthoic acid. 8 Amino-1-naphthoic acid. 5-Amino-2-naphthoic acid. 7-Amino-2-naphthoic acid. 8-Amino-2-naphthoic acid. Furthermore side-chain or nuclear substitution products of aminonaphthoic acids may be employed, for example the N-alkyl sub stitution products (obtained for instance by treatment of the corresponding hydr0Xy- .naphthoic acids under pressure with alkylamines) or the amino, oxy or halogen substitution products.

Instead of amino anthraquinones, substitution products thereof may be employed, for example alkyl, alkoxy, carboxy, amino, halogen, hydroxy, nitro or acidyl amino nuclear substitution products thereof.

Diaminoanthraquinones may be tetrazotized and coupled with two molecules of an The dyestufi gi e r d-brown shades and has the plfqb blc for- I d i l i l V: :V V

aminonaphthoic acid or substitution product thereof, or with one molecule of an aminonaphthoic acid or substitution product thereof and one molecule of a diiferent coupling component.

What I claim and desire to secure by Letters Patent is 1. As new products, azo dyestuffs of the probable formula R (N=NR where n is 1 'or 2, R an anthraquinone nucleus and at least one R is an amino naphthoic acid.

2. As new products, azo dyestuffs of the probable formula R (N=N-R 1,, Where n is 1 or 2, R an anthraquinone nucleus and at least one B is a beta-amino naphthoic acid.

3. As new products, monazo dyestuifs of the probable formula R N=NR where R is an anthraquinone nucleus and R is an amino naphthoic acid.

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4;. As new products, monazo dyestuffs of v the probable formula R N N R where R; is an anthra'quinone nucleus and R is a beta-am no naphthoic acld.

5. Process for the production of new azo dyestuffs, comprising diazotizing an anthraquinone compound containing at least one diazotizable amino groupandcoupling with an amino naphthoic acid.

6. Process for the production of new azo dyestuffs, comprising diazotizing an anthraquinone comp'oundcontaining at leastv one diazotizable aminogroupand-coupling with a beta-amino naphthoic acid.

7. Process for the production of new monazo dyestuffs, comprising diazotizing an anthraquinone compound containing at least one diazotizable amino group andcoupling with an amino naphthoic acid.

8. Process for the production of new monwazo dyestuffs, comprising diazotizing an anthr'aquinone compound containing at least one diazotizable amino group and coupling with a beta-amino naphthoic acid.

In testimony whereof I have hereunto subscribed my name.

GEORGE HOLLAND ELLIS. 

